Japanese Patent Application Laid-open No. H5-345156 discloses a conventional electrostatically atomizing device for generating charged minute water particles of nanometer order (nanometer-size mist). In the device, a high voltage is applied across an emitter electrode, supplied with water, and an opposed electrode, to induce Rayleigh breakup of the water held on the emitter electrode, thereby atomizing the water. The charged minute water particles thus obtained, long-lived and containing radicals, can diffuse in large amounts into a space. These water particles can thus act effectively on malodorous components adhered to indoor walls, clothing, or curtains, to deodorize the same.
However, the above device relies upon a water tank containing the water that is supplied to the emitter electrode by capillarity, and thus the user has to replenish the water tank. In order to obviate this procedure, there could be provided a heat-exchanging section for condensing water by cooling the surrounding air, such that the water condensed by the heat-exchanging section (condensed water) is supplied to the emitter electrode. This approach, however, is problematic in that it takes at least several minutes to condense water at the heat-exchanging section and to feed the condensed water to the emitter electrode.
If water for electrostatic atomizing could be formed, as condensed water, on the emitter electrode by cooling the latter, there would be no need for water to be supplied to the emitter electrode. This approach, however, involves problems as regards emitter electrode cooling. If the emitter electrode cools excessively, excessive condensed water may adhere to the emitter electrode, while insufficient  emitter electrode cooling may prevent condensed water from forming on the emitter electrode, precluding atomization as a result.
Since the discharge voltage is constant, more condensed water implies a greater discharge current, while less condensed water implies a reduction in discharge current. Therefore, an appropriate amount of condensed water can be ensured at all times on the emitter electrode by monitoring the discharge current and by adjusting the degree of cooling of a cooling means in accordance with the discharge current value. When such control is performed also during the time that it takes for condensed water to form on the emitter electrode, however, there arise problems in that control may be impossible, or in that hardly any condensed water forms on the emitter electrode.